HORSE CANYON. Horse Canyon begins in the Black Gap Wildlife Management Area six miles northwest of the Gerstacker toll bridge over the Rio Grande in southeastern Brewster County (at 29°32' N, 102°52' W) and runs southeast for five miles to its mouth on the Rio Grande, nearly two miles northeast of the bridge (at 29°28' N, 102°49' W). The canyon runs through flat terrain with local shallow depressions, surfaced by clay and sandy loams that support water-tolerant hardwoods, conifers and grasses. Towards its mouth it crosses steep to gently sloping terrain surfaced by shallow to moderately deep soils that support scrub brush and grasses.
The following, adapted from the Chicago Manual of Style, 15th edition, is the preferred citation for this article."HORSE CANYON," Handbook of Texas Online (http://www.tshaonline.org/handbook/online/articles/rkh05), accessed December 21, 2013. Published by the Texas State Historical Association.